Sunday, February 26, 2006

Skittles Part 2

I am getting back into the circles groove/grind. For some reason blitz is helping, keeping things fun.

In my last game, I had a sloppy opening as Black but then played the longest combination of my career. Under the time pressure I miscalculated - I thought I had either checkmate or was going to be up a major piece. Sigh. I will take longer, slower win, especially considering that my opponent could have earned a draw via perpetual check earlier!

24...Rxh2+! {sacrifice to open the h file}25. Kxh2 {forced}25...Rh8+ {White's King is immobilized}26. Bh3 {forcing the White Bishop into yet another absolute pin}26...Nf6 {threatening check}27. Rd1 {threatening the Black Queen - the best move for White}27...Ng4+28. Qxg4+ {a forced sacrifice}28...fxg4 {doubly attacking the pinned Bishop}29. Rxd4 {gaining back some material, but leaving that Rook enprise}29...Rxh3+30. Kg130...Rxg3+ {netting another pawn before taking the hanging White Rook}31. Kf231...Rf3+ {protecting the Black Rook with tempo}32. Ke232...cxd4

{Now White can get a pawn back, but his second rank weaknessultimately concedes two more pawns.}33. Rg5+33...Kf6 34. Rxg4{Here it would have been stronger to push the d4 pawn, butI found a simpler trade-down plan along Black's seventh rank}34...Rc3 35. Rg8 Rxc2+ 36. Kd1 Rxa2

Wednesday, February 22, 2006

Skittles

My blitz rating just hit 1450, and I credit the circles. It doesn't seem all that long ago that I thought hitting 1200 blitz was an accomplishment. I don't consider blitz to be real chess, but it's fun. Surviving the time-pressured, mistake filled, frenzied play can really give me a high, when I win that is. Looking at blitz games afterwards continues to highlight BIG gaps in my play, as well as putting things into perspective. Take this position for example:

Black to Move: is c1=Queen good?

It's actually horrible, and that's just what I did. To prove the point that chess is all about mistakes, my opponent ignored the perpetual check:41.Qe8+ Kg7 42.Qe7+! Kh6 43.Qh4+ Kg7 44.Qe7+ etc. 1/2-1/2

2b3k1/7p/2Q3p1/4bp2/4p3/4q1P1/6KP/2q2B2 w - - 0 1

I guess a win is a win.

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I am starting circles 5 through 7 on TCT Step 3. My focus is on keeping a "game-like" mental approach throughout, which is more difficult than it might sound.

I wanted to say I have noticed that there are many and interesting games and discussions posted recently in the chess blog-o-sphere. Very cool :-D.

Saturday, February 18, 2006

Step 2 Complete

That's a relief. The last 200 problems were the slowest. I gave each problem more real-game type consideration, hoping to get more out of this last bit of the process than I would relying purely on memorization or CTS blitz-like mentality.

I am taking a short break before Step 3.

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I ran into this game recently and was baffled attempting to follow it. The first surprise was that up to move 17 it follows book. Here is the game, followed by Fritz's analysis:

Through no fault of my own I won an incredibly inaccurate Cochrane Gambit blitz game as Black. If you look at the main line of this opening, you might conclude that it was concocted by space aliens. Granted, it can be a real test of Black's defensive skills, and even more so in blitz.

Luckily, my opponent gave me an almost obvious checkmate opportunity, an opportunity which I squandered by offering up my Queen instead of my Rook. Not to be outdone, my opponent let me keep my Queen, continuing on embarrassingly until he finally handed me a checkmate so obvious I couldn't refuse. This last blunder was avoided a position where he was materially behind but had a big pawn center, i.e. objectively lost but still with promotion threats. Here is the checkmate position and solution right underneath:

Saturday, February 11, 2006

Nearly Through TCT Step 2

It's approaching the finish line on this circle stuff. At this stage I have shifted into taking my time with each problem so I burn in the most useful aspects of each position. For fun I have been sneaking in some blitz, tried to make heads or tails of handling the Blackmar-Diemer Gambit as Black, and finally finished the third game in the McDonald book. In that game between Kasparov and Bacrot, Black gets into an incredibly passive situation for awhile before crumbling. I hate that! In a manner that seems very parallel to what Pawn Sensei recently posted about when GMs blunder, I'll say that seeing one of today's top players suffer this way puts my own experiences into a more positive perspective.

Thursday, February 02, 2006

Simultaneous Advantage

Introduction

Tactical Terminology

Since reading The Mammoth Book of Chess I have been using Burgess' tactical terminology in puzzling through difficult chess positions. This helps when I cannot understand an answer to a tactics problems, or when get stumped reading annotations comprised of variations with no supporting text. I hope that explaining these to myself "verbally" I will grasp the idea better.

Along the way, I have become somewhat non-standard in my tactical language. Naming tactics differently and seeing multiple tactics where others don't are my two biggest deviations from the norm. I have investigated both of these issues deeper, and this has led me to developing a new system for describing tactics.

Part I

Which Tactic is This?

White to Move

Tasc Chess Tutor, Step 2 Exercise 5b, #9Answer: Bxf7+

What you call the Bxf7+ sacrifice depends on how you were taught. I seems ambiguous that might be called oneor more of the following:

Decoy

Chasing

Overworked defender

Overloaded defender

Deflection/Distraction

The most common response is that this is a decoy. This is like saying, "Moving the Black King to capture the Bishop is fatal for Black's Queen." I view this as a deflection, which is like saying, "The Black King's most important duty is to defend the Queen, and yet he moves away.". If the Black King was a Queen, it would look more like an overworked piece. I could see how someone could view these as chasing or overloading.

Aspects of Multiple Tactics

Another ambiguous area of is multiple tactics. I see this everywhere, or perhaps more accurately aspects of multiple tactics, although it's rarely described that way. Take this obvious checkmate in two for example:

White to Move

Rxh3+ gxh3 Rh3#

Four aspects seem to stand out in this position:

Rxh3+ gets the g3 Rook out of the way of the d3 Rook, getting White ready for the final checkmate move

Rxh3+ sacrifices a Rook for a pawn, a pawn that block's part of the h-file

gxh3 draws a defender away from protecting the h3 square

gxh3 turns a defender into a target on the h3 square

What do you call this kind of sacrifice for checkmate? Putting that question aside, is this multiple tactics? There is no hard and fast rule on what qualifies as multiple tactics, and few would give it that label. I personally like calling this outnumbering. Still, using a more common name for the initial Rook sacrifice leaves out those four aspects.

Part II

Simultaneous Advantage

Because of the two above ambiguities, I was at an impasse. My tactical descriptions were going to differ from the norm, and labeling many moves as multiple tactics would make things worse. As well, using other umbrella terms wasn't a satisfying solution, and that approach seemed too broad. I needed something else.

I focused on breaking things down further. I originally set out to categorize everything I knew about tactics: material gain, tempo related tactics like zugzwang and zwischenzug, forced mates, etc.. Just talking about forced moves brought up essentially forced moves, and so on. Unfortunately this list was too vast.

I finally focused exclusively on forced checkmates that start with a sacrifice. I set out to make an unambiguous vocabulary that was capable of tracking all of the tactical aspects in these positions.

I ended up with a simple 2x2 grid and viola all the parts began fitting together. I started with this:

Simultaneous Advantage When Sacrificing for Checkmate

move

away from a square

onto a square

attacking piece

advantage(s)

advantage(s)

defending piece

advantage(s)

advantage(s)

This grid combines the attacker's plusses and the defender's minusses. An advantage is anything in the position that changes beneficially for the attacking side:

the attacker's liability becomes a neutrality

the attacker's liability becomes an asset

the attacker's neutrality becomes an asset

the defender's asset becomes a neutrality

the defender's asset becomes a liability

the defender's neutrality becomes a liability

The grid pinpoints the exact moment that an advantage is obtained. Each box has zero to many advantages written in it.

Here is my current draft of the advantages list and three detailed examples using it:

move

away from a square

onto a square

attackingpiece

clearing a square

evading a threat

discovering:

forcing with check

forcing with zugzwang

mobilizing attackers

outnumbering to attack

outnumbering to block

pinning - absolute

preventing counterattack

removing all of theKing's flight squares

removing some of theKing's flight squares

threatening captures

threatening check

resulting checkmate threat

blocking a line

blocking a square

breaking a pin

capturing a defender

capturing cover

forcing with check

forcing with zugzwang

mobilizing attackers

outnumbering to attack

outnumbering to block

pinning - absolute

preventing counterattack

removing all of theKing's flight squares

removing some of theKing's flight squares

threatening captures

threatening check

resulting checkmate threat

defendingpiece

clearing a square

discovering:

mobilizing attackers

outnumbering to attack

outnumbering to block

pinning - absolute

preventing counterattack

removing all of theKing's flight squares

removing some of theKing's flight squares

threatening captures

threatening check

swapping a threat

threatening check

withdrawing counterattack

withdrawing defense:

outnumbering to attack

outnumbering to block

resulting checkmate threat

blocking a line

blocking a square

capturing the maskingpiece

moving into capture

moving into anabsolute pin

moving King onto amore vulnerable square

removing all ofthe King's flight squares

removing one ofthe King's flight squares

swapping a threat

resulting checkmate threat

Notes:

It is assumed that the best offense and defense is used.

"Discovering" means a blocking (or masking) piece is moved, increasing the influence and mobility of one or more long-range attacking pieces. When this action occurs, one or more advantages are ascribed to it. "Discovering" is being used broadly here, as it includes situations where two long range pieces that form a battery move away from one another and where a Rook or Queen is behind a pawn that advances forward.

"Moving into an absolute pin" inherently implies that the piece has also moved into a capture that gives check, and this is treated differently from "moving into capture". Having both of those in a box means that in addition to the pinning threat, one or more other pieces are threatening to capture.

"Outnumbering" is similar to winning material by outnumbering an opponent's piece with more attackers than defenders. Here it means an attack on a square, so capturing is not required. The idea is that with more attackers than defenders trained on that square, an attack or interfering block from that square will succeed. This happen at any point, on either the attacker's move or the defender's move. If outnumbering happens on the defender's side, it might be thought of as overloading.

"Preventing counterattack" could be broken down further: preventing checkmate, check, perpetual check, perpetual chase, threats to capture pieces necessary for the final checkmate position, and threats to block pieces necessary for the final checkmate position. That list also applies to "withdrawing counterattack" advantage, which additionally includes unpinning one of the attacker's pieces, meaning both relative and absolute pins.

In "threatening check", the term "check" means threatening the defender's King with check or checkmate. When it occurs, further calculation is required to determine if it truly is a checkmate threat.

swapping a threat- The capture on a4 givesthe Black King a flightsquare and prevents b5#,but in the process Blackhas created anothercheckmate threat from theWhite Queen on the a-file

threatening check- Qxa4

resulting checkmate threat: Qxa4#

White:

b5#

------

Qxa4#

discovering:

removing all of theKing's flight squares- the Bishop on d2keeps the BlackKing immobilized

------

#------

capturing cover

removing all of theKing's flight squares

#

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I find it striking that the first example has something in each of the first four boxes, something that it shares with the second example. Also striking is how few advantages were in boxes the third example, ...Rxc6 variation; most of the required advantages for checkmate were there to begin with, so this makes sense.

Part III

Common Knowledge

A well-disciplined player will typically do several things each turn:

Determine if he can checkmate is opponent

Determine if he must stop a checkmate threat

Play for advantages appropriate to the position and stage of the game

In checkmate situations material superiority is meaningless, and as such it really isn't discussed in depth in chess books. Nonetheless, I think it deserves consideration. It seems that (at least) two modes of thinking are employed each turn, which I will call "checkmate thinking" and "non-checkmate thinking". These modes are very different, and confusion usually spells disaster. Not using checkmate thinking when it's an important part the position leads to mistakes: miscalculating checkmate threats because it looks like it loses material, ignoring checkmate threats for one side, etc.

Material

Material advantage is the biggest winning factor in non-checkmate thinking because it often leads to a win. The relative values of each piece is well known in its most simplistic form:

Material Values

I think the other mode of thinking deserves its own table:

Material Values in Forced Checkmates

It's almost simpler to consider checkmate-thinking values, as it's a specific all-or-nothing ordeal (the "8" symbol on it's side means infinity). Having some material be worth 0 implies alot of things. Gain and loss have no meaning, and there is no way to sacrifice material per se, leaving only participants in the final checkmate position as having value.

Rewording

I started this investigation out mapping out all the different possible sacrifices for checkmate. I thought I was getting to the conclusion that all of these appear to be sacrifices for position, a well known idea.

Based on material devaluation in checkmates, I thought of changing the conclusion and call them exchanges for position. This would make the overall idea akin to even trades in non-checkmate situations, so giving up a full Queen potentially could be considered equal to getting a Queen for a pawn.

Next I thought, "What if the attacker doesn't sacrifice to start with, or maybe simply never sacrifices to achieve checkmate?" The grid still worked. Perhaps these all were forced checkmates.

Finally, allowing for the possibility that the defense could make an unforced blunder, it seems like these are simply checkmates. So here is the same grid, different title, now without the requirement to sacrifice or trade material:

Simultaneous Advantage in Checkmates

move

away from a square

onto a square

attackingpiece

clearing a square

evading a threat

discovering:

forcing with check

forcing with zugzwang

mobilizing attackers

outnumbering to attack

outnumbering to block

pinning - absolute

preventing counterattack

removing all of theKing's flight squares

removing some of theKing's flight squares

threatening captures

threatening check

resulting checkmate threat

blocking a line

blocking a square

breaking a pin

capturing a defender

capturing cover

forcing with check

forcing with zugzwang

mobilizing attackers

outnumbering to attack

outnumbering to block

pinning - absolute

preventing counterattack

removing all of theKing's flight squares

removing some of theKing's flight squares

threatening captures

threatening check

resulting checkmate threat

defendingpiece

clearing a square

discovering:

mobilizing attackers

outnumbering to attack

outnumbering to block

pinning - absolute

preventing counterattack

removing all of theKing's flight squares

removing some of theKing's flight squares

threatening captures

threatening check

swapping a threat

threatening check

withdrawing counterattack

withdrawing defense:

outnumbering to attack

outnumbering to block

resulting checkmate threat

blocking a line

blocking a square

capturing the maskingpiece

moving into capture

moving into anabsolute pin

moving King onto amore vulnerable square

removing all ofthe King's flight squares

removing one ofthe King's flight squares

swapping a threat

resulting checkmate threat

Addendum

The name "Theory of Simultaneous Advantage" came out of the realization that the most difficult tactical moves frequently involve multiple things happening on just one move. It is still under development, and it currently appears to be more like a vocabulary system than a theory. One thing that I am stating that does appear to constitute a theory is this:

The only way to achieve checkmate is through Simultaneous Advantage

For the most part, this system constitutes a reorganization of well-known chess principles. I believe this theory could be expanded to cover other parts of the game beside checkmate, perhaps with different grids to cover other types of advantages that occur in other sections of the game. The grids would serve as a reference, setting out a baseline of all the plusses one might encounter. In a complete treatment of a line, two grids and two corresponding advantage lists would be needed.

In terms of the opening, the most instructive games are filled with moves that fit right into this kind of theory. Just think about the typical annotated game after 1. e4 e5 2. Nf3 Nc6 3. Bb5 . Authors rave about White's castling preparation while threatening to inflict doubled pawns upon Black and hang the e5 pawn. This has been exhaustively studied, and it turns out that the 5. Nxe5 threat can be dealt with. Usually the prospect of handing Black a two Bishop advantage usually makes White choose not to capture on c6 on the next turn. Viewing the position in an immediate sense, the two Bishop advantage wouldn't immediately become a meaningful plus in the postion for Black if White trades his Bishop for the c6 Knight, so I can see it argued that White has achieved at least two if not three simultaneous advantages on move 3.

Normal Checkmates in the Theory of Simultaneous Advantage

To achieve checkmate the advantages all of these advantages must be accrued by the mating side before the last move:

The mating side has1. the move2. mobility to move the mating piece to the the mating square or, in the case of a discovered mate, has the mating piece on the mating square and has mobility to move masking piece off the mating line (i.e. it's not trapped)3. a way out of check if he is in check. This move will deliver a discovered mate by having the mating side's King either capture the checking piece or move safely away leaving the defending side's checking piece, leaving that piece unable to stop the checkmate because of an absolute pin. This is here for completeness, as the situation is extremely unlikely to occur naturally:

White to move, and Black cannot interpose his pinned Queen to stop mate in 1.

Returning to the list of advantages...The defending side has1. a King must on a vulnerable square2. either all of his King's critical flight squares eliminated by his own pieces, the edge of the board, or being controlled by a mating side piece or is about to have them completely removed as a result of the upcoming mating move3. no effective attack on the mating square4. no available piece that can interpose between the mating square and the King in long-range checkmates

TacticsIn closing, here is a rough mapping of where common tactics fit on the grid:

Move

... away from a square

... onto a square

my piece

discovered attacks

line opening

square clearance

windmill

chasing

destruction

double attack

fettering

fork

offensive interference

offensive interposition

overloading

overworking

pin

prophylaxis

removing the defender

sacrifice

skewer

trapping

x-ray

zugzwang

zwischenzug

his piece

chasing away

deflection/distraction

unpinning

decoy

interference

interposition

self blockade

Sources:

Tasc Chess Tutor version 2.01,Tasc B. V. Holland 1995-1999

The Mammoth Book of Chess by Graham Burgess, Carroll And Graf 1997, 2000

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I done my best to make this accessible and understandable.

If you think anything has been unclear or want to leave feedback,please leave a comment.